Health warning on antibiotic resistant Shigella

What is the issue?

There is an increasing number of shigellosis cases infected with strains of Shigella bacteria that are multi-drug resistant (MDR), or extensively-drug resistant (XDR), across Europe and several other countries, as well as in Australia. XDR Shigella is not susceptible to key recommended antibiotics including penicillins, cephalosporins, aminoglycosides, tetracycline, sulphonamides, quinolones and azithromycin. Many cases are occurring among returned travellers and men who have had recent sexual contact with other men.

Although shigellosis is usually self-limiting, antibiotic treatment may be required for severe infection and priority cases. However, antibiotic resistant infections have limited treatment options and can be spread from person-to-person.

Who is at risk?

Men who have had recent sexual contact with other men and returned travellers from countries with high rates of infection are at higher risk of contracting shigellosis, including from MDR and XDR Shigella strains.

Symptoms and transmission

Shigellosis is characterised by an acute onset of diarrhoea, fever, nausea, vomiting and abdominal cramps. Stools typically contain blood, mucus or pus but some people only experience watery diarrhoea. It is usually a self-limiting infection, however in certain at-risk individuals, such as young children, older people and those who are immunocompromised, it can be potentially serious. Complications of dehydration, electrolyte disturbance and progressive infection can occur.

Shigellosis is highly contagious and is mainly transmitted through the faecal-oral route, including during sexual contact. Symptoms usually develop one to three days following exposure but can occur from 12 hours to one week in some cases.

Cases remain infectious while the Shigella bacteria continue to be shed in the stools. This can last for up to four weeks after symptoms resolve.

Treatment

In most cases only supportive treatment, including plenty of fluids, is required. Due to the concern of increasing antibiotic resistance, antibiotic treatment should be reserved for severe infection and priority cases.

Recommendations

For clinicians

Clinicians should include stool culture and antibiotic susceptibility tests when investigating for shigellosis.

Antibiotic treatment should be reserved for severe infection or those who are immunocompromised and for priority cases where there is a risk of onward spread to at-risk individuals. Priority cases include:

• Food handlers
• Childcare workers
• Healthcare workers
• People living or working in a residential facility, such as aged care facilities, disability group homes, prisons, and other residential facilities
• Children younger than six years.

Antibiotic choice should be based on susceptibilities and advice should be sought from the local infectious disease department or microbiologist as antibiotic resistance varies by region and over time.

Anti-motility medications are contraindicated as they may prolong symptoms and bacterial shedding.

Local Public Health Unit are following up people diagnosed with MDR and XDR Shigella infections and their contacts to provide advice about symptom monitoring, testing and exclusion requirements.

Patients should be advised to maintain good hygiene and safer sex practices, avoid preparing food for others and be excluded from work if they are a priority case until cleared by their Local Public Health Unit.

Clinicians and pathology services must notify the Department of Health of any cases of shigellosis within five days of diagnosis. Notifications can be made online or faxed on 1300 651 170.

For the public

People with shigellosis should maintain good hygiene practices, especially handwashing after using the toilet and before eating or preparing food. Do not prepare food for others, enter pools or visit high-risk settings (such as childcare, healthcare and residential facilities) until 48 hours after symptoms resolve. Kitchen and bathroom surfaces should be regularly cleaned.

People with shigellosis can prevent the spread of infection through safer sex practices, which include:

• Abstaining from sex while symptomatic and for one week after symptoms completely resolve

In addition, for a further two weeks:

• Using barrier protection (such as condoms and dental dams) during sex
• Limiting sexual activities with faecal-oral exposure, such as rimming, which may significantly increase the risk of spreading infection
• Showering and washing hands before and after sex.

People who work in occupations where there is a risk of onward spread to at-risk individuals should be excluded from work until advised by their Local Public Health Unit. These workers include food handlers, childcare workers, health care workers, and people who work in a residential facility such as aged care facilities, disability group homes, prisons, and other residential facilities.

People living in a residential facility should be isolated from other residents if possible until 48 hours after symptoms resolve.

Children with shigellosis must be excluded from childcare and primary school until 24 hours after symptoms resolve.